Dropbox have just updated their Android app to 2.1.4. Now this may seem like a small update, but there is a key feature here which is unfortunately only available on ICS right now, which enables you stream videos. That's right, you can now stream videos, movies, tv shows and so on right from Dropbox on to your device, provided you have a good enough internet connection. Some people are saying they were able to stream HD movies right from their Dropbox on to their device and watch them without any problems.
Hopefully this key new feature will be coming to other devices soon. But I can see why they're trying it on ICS for now because most ICS devices are the most powerful phones on the market right now.